Invert a tall glass or jar in a dish of water, and place a lighted taper under it ; as the taper consumes the air in the jar, its pressure J becomes less on the water immediately under ?the jar ; while the pressure of the atmosphere on the water without the circle of the jar remaining the same, part of the water in the dish will be forced up into the jar, to supply the place of the air which the taper has consumed. Nothing but the pressure of the atmosphere could thus cause part of the water to rise within the jar above its own level.— —-